Method and apparatus for burning fuel



' June 4, 1929.

E. P. WETMORE METHOD AND APPARATUS FOR BURNING FUEL original Filed oct. 25, 1924 sie / INVENToR.

, ATTORNEY Patented 'June 4, 1929..

EARL P. vWIE'JJNIOIR'IEI, OF CONCORD, MICHIGAN, ASSIG-NOR TO THE ANOILCOAL'BURNER CO., 0F TOLEDO, OHIO', A CORPORATION OF DELAWARE. l

.METHOD AND APPARATUS lOl'x. BURNING FUEL.

Application led October 23, 1924, Serial No. 745,312. Renewed March 17, 1928.

rlhis invention relates toa fuel burner, and,

more particularly, to a burner adapted to yproduce a readily combustible suspension in air of fuels of a semi-solid nature, such as the stiff pastes formed of solid and liquid fuels, or of other plastic fuels of similar nature.

Composite fuels of the type indicated are commonly formed of the minute particles of -pqwdered fuel, from which the ash content may have been removed inwhole or in part, and of a liquid. fuel which surrounds the par. ticles with a film or layer of oil and serves to unite them into a coherent paste of a nature intermediate that of the solid and liquid fuels of which it'i's coniposed and having characteristics different from those of either. of their constituents, being usually of sufficient stiffness that it does not flow readily, and' may be burned on a suitable lgrate in the manner of solid fuels. Because ofthe` greater flexibility in controlling combustion and in the consumption of the fuels, when fuels are burned in ames in the manner of fluid fuels, and the resulting greater efficiencies' andeconomies in combustion,it is however highly desirable to burn such fuelsby atomizing and diffusing f them in a current of air, so that they may be quickly ignited and burned, and then projecting the mixture of commjngled air and fuel into a combustion chamber in whichits combustion may be completed. Owing to the physical characteristics of the composite fuels of the above mentioned types, in which the separate particles of solid fuel are tenaciously Aheld together by their enveloping 'films of oil, they can not be handled in the same manner as liquid fuels, which flow readily-and are easily broken up to a mist, nor in the manner of pulverizedvfuels, which are already in a fine state of division and partly mixed with air.

An object of my present invention is to pro,-

' vide a method and apparatus by which fuels of the above mentioned types and characteristics maybe divided and'suspended in a current of air and enabled to b e burned in the manner of fluid fuels. l

Another object of the invention is to provide an apparatus in which fuels of the above indicated types may be finely divided and suspended in a current of air in a condition to be readily burned andthe quantity of air automatically controlled and regulated in accordance withthe requirements of the fuel.

A further object of the invention is to provide an apparatus in which the fuel paste is positively and mechanically separated into finely divided particles and efliciently dispersed into a gaseous medium.

A still furtherobject of the invention is to provide an apparatus by which composite fuels of the above mentioned types may be fed at a uniform and readily controlled rate and dispersed into air in a state of division to be readily ignited and burned. With these and other objects in view, which will appear from the following detailed description' of the invention, the invention comprises the method and apparatus described and set foi-thin the following specification and claims. The various features of the invention are v" yillustrated in the accompanying drawings, in which: A I l Figure l is a plan view, partly in section, of a fuel 4burning apparatus embodying a preferred form of my invention,

Figure 2 is a longitudinal, elevational sectional view 'of the burner apparatus taken on line 2 -2 of Figure lfand Figure 3 is a front view of a fuel separatv ing or disintegrating and dispersirfg device forming a part, of the fuel burning apparatus. In my present invention, a current or blast of 'air is produced in a suitable conduitand delivered to a mixing chamber into which a supply of fuel is fed and divided and dis-I persed in the air, and from which it passes with the suspended fuel into a suitable combustion chamber. A supply of fuel paste is forced under a substantially uniform pres# sure into' an annular chamber encircling thel l, air conduit, from which it passes through an annular openin or other suitable openings into the mixing chamber. The converging, inner, annular edge or edges of this fuel paste is continuously sheared off in thin particles and carried into the blast or current of air by means lof cutting or shearing 100 blades whichare preferably. rotated at the l Dinner edge of the fuel andJas the fuel is forced into contact with them, serve to sepa-A rate the fuel into fine particles or into the particles of solid fuelof which the paste is formed. The cutting blades also serve to thoroughly mix and suspend the fuel in the blast of air. The rate of supply of the fuel is controlled as by controlling the width of the orifice or openingv through which it is forced 110 in the air blast and the velocity ofthe air panying drawings, a blast of air is driven forwardly through a cylindrical conduit 10 by means of a fan'll, connected to a driving motor 12 or other driving means by means of a flange coupling 13. The air driven forwardly by the fan 11 passes through a narrowed or converging front end opening 14 of the conduit 10 into a mixing chamber 15 in which it receives a supply of fuel in finely divided form and carries this fuel suspended in a fine state of division into a combustion 'chamber 0r-nozzle 16 in which it may be ignited and directed t0 a suitable furnace or other apparatus. y

A supply of fuel to befed into andv divided and dispersed in the l.air blast, is charged into a hopper 17, to the rear of the conduit 1U. and sinks downwardly intoY a conveyor.

tube 18, on the rear portion of which the hopper is mounted.- Y The rear end of the tube 18 isv closed by means of a plate 19 bolted to the end of the tube, and the front end curves upwardly at 20 and merges and leads into an annular chamber 21, encircling the front converging end 14 of theI conduit 10. The fuel received in the tube 18 is forced forwardly in the tube and into the chamber 21 by means of a conveyor screw 22 supported on'a shaft 23, the front end of which is joui'- nalled in a bearing 24 in the upwardly curving portion 20 of the tube and the rear end of which extends rearwardly through a bear- -ing 25 in the plate 19 and is driven by means of a worm 26 and gear 27 mounted on the projecting rear end of the shaft. Sufficient clearance is provided between the screw22 and thel inner surface of the tube 18 so that the fuel is delivered-to the annular chamber 21 under a substantially uniform pressure, any greater pressure being relieved by the slip between the screw and tube.

VFrom the chamber 21 an annular sheet of fuel is.4 forcedf forwardlyA and inwardly through an annular opening 28 formed between an annular edge 29 at the juncture of the surfaces of the mixing chamber 15 and the chamber 21,'and a tapered outer surface- 30 of the front. end of the conduit cylinder 10. As the annular layer of fuel is pressed through the opening 28, thin strips or particles are sheared from .its advancing front edge and thrown into the forwardly moving blast 0f air by means of a number of rotating blades 31, four blades being shown by way of example. The front faces 32 of the j blades 31 are at an angle to the direction of `movement of the ,fuel so that the fuel slices or particles are cut from the bodyof volume of the air.

the fuel and thrown The blades 31 are preferably mounted on a central hub 33 having its rear face 34 curved outwardly to direct the air fromthe conduit 10 towards the outer portion of thel mixing chamber 15 into intimate contact with the coal particles and insuring the distribution of the co'al particles throughout. the

The air thus passes forwardly along the flaring face 34 and between the blades 31 and thus into intimate contact with the fuel being sheared or cut from the advancing sheet.. mounted on a shaft 35 which extends from the fan 11 and is journalled in a bearing 36 supported centrally within the'conduit cylinder 1() by means of three radial spiders 37 nd is thus drivenat the same speed as the As the pressure of the fuel within the chamber21 is substantially constant, the rate at which the fuel is supplied through theopeni'ng 28 to the mixing chamber 15 is governed by the width of the opening 28. The width of the opening 28 may be varied by moving the cylinder 10 forwardly or rearwardly to move the surface 30 towards or from the edge 29. For this purpose, the cylinder 10 is slidably mounted in a cylindrical wall 38r eXtend- .cylinder 10 by means of an actuating handle I41 or other means, which may be actuated by hand or by a pressure regulator or other automaticcontrol means, to adjust the supply of fuel in accordance with the heat or energy dev'ruands of the burner..

The hub 33 is preferably i ing rearwardly from the rear edge of the an- For the most efficient and economical combustion, it is desirable to adjust the velocity or quantity of air supplied in the air blast in accordance with the fuel supply so that just suiicientfair maybe supplied to effect the completecombustion of the fuel., For this purpose, the speed of rotation of the motor 12 and accordingly of the fan 11 is controlled by means of a control rheostat 42, which is, in

turn,l controlled by the handle 41, or other means controlling the rotation of the pinion 39, so that, as the pinion39 is rotated, the resistance in the rheostat 42 is varied and the velocity of the air blast proportioned to the width of the opening 28.

The apparatus may be built or constructed in any suitable manner or form. As indicated in the example shown in the accompanying drawmgs, the conveyor tube -18, annular chamber 21, mixing chamber 15, nozzle or inder is then mounted in and supported in the wall 38. The apparatus may be mounted onA supporting feet or legs 43 on which. the tube 18 rests.V As indicated, the motor 12 and fan 11 are mostconveniently mounted within and movable with the cylinder 10.

As changes of construction could be made within the scope of the invention, it is desired that all matter contained in the above description or shown in the, accompanying drawingsshall be interpreted as illustrative and not in a limiting sense.

Having described my invention, what I claim and desire to secure by Letters Patent is:

1. A method of burning plastic fuels which comprisesyfeeding an annular sheet of plastic fuel inwardly and forwardly, shearing particles from the advancing edge ,of said sheet,

and passing a current of air within said sheet of fuel and deflecting it outwardly to the edge .of fuel being sheared.

2. A method ofburning plastic fuels which comprisesfeeding an annular sheet of plastic fuel inwardly and forwardly, controlling the rate of feeding of said fuel, shearing particles from.- the advancing edge of said sheet, passing a current of air Within Asaid sheet and deflecting it outwardly to the edge of fuel being sheared to pick up and disperse said particles, and controlling the rate of supply of air in accordance with the rate of feeding of fuel.

- ecting itoutwardly over the edge of said fuel 3.- A method of burning plasticfuels which comprises feeding an annular sheet of plastic fuel inwardly and forwardly under substantially constant pressure, controlling the thickness of said sheet, shearing particles .from the advancing edge of said sheet, passing a current of air within said sheet and debeing sheared lto pick up and disperse said particles, and controlling the velocity of saidair current in proportion to the thickness of said fuel sheet.

4. Apparatus for burning fuels ofthe type' indicated which comprises, 'means for feeding fuel 1n an annular lconverging sheet,` means for passing a current of air within saidannu- `lar sheet, and means for shearing and dispersing particles from the advancing edge of said sheet into said current of air.

5. Apparatus for burning fuels of the ty indicated which comprises', means for feeding fuel in an annular converging sheet, means .for passing a current of air within said annularslieet and delecting it outwardly over the advancing edge of said fuel sheet, and means for shearing and dispersing particles from said sheet into said current of air.

rent.

6. Apparatus for burning fuels of the type indicated which comprises means Afor feeding fuel in an annular converging sheet, means for controlling the rate of feeding of said fuel, means for passing a current of air within said .annular sheet and deflecting it outwardly over the advancing edge of said sheet,

outwardly over the advancing edge of said sheet, means for controlling the Avelocity of said ai'r current in direct relation to the thickness of said fuel sheet, and means fordetaching particles of fuel .from the advancing edge of said sheet and dlspersing them into said air'current.

8. Apparatus for burning fuels which comprises an annular fuel feeding chamber, an

lannular opening extending inwardly and forl wardlyl from said annular chamber,- fuel' cutting blades rotatable across the forward inner edge .of said opening in the path of fuel therefrom, and means for blowing a current of air forwardly over the inner edge of said open-` ing.

f). Apparatus for burning fuels which comprlses an annular fuel vfeeding chamber, an

annular opening extending inwardly and forl l wardly from said, annular chamber, fuel cutv ting blades rotatable over the forward inner edge of said opening in the path of fuel therefrom, means for blowingfair forwardly, centrally of said annular chambemand means for deflecting said air outwardly to the edge of said opening. 10. Apparatus for burning fuels comprises an annular fuel feeding chamber,

an annular opening extending inwardly and jforwardly from said annularI chamber, means for controlling the rate of feeding-of fuel 1- n v rotatable over the `forward inner edge of said i through said opening, fuel cuttingblades whichA 110 opening in the path of fuel therefrom,fmeans i.l

for blowing air forwardly within the annular edge of said opening in the pathof said blades, and means for automaticallyadjusting the velocity of said air current in relation to the rate of feeding o'f said fuel.

11. Apparatus for burning fuels "which comprises an annular feeding chamber, an annular opening extending inwardly andl forwardly from said annular chamber, means for supplying fuel to said feeding chamber under a substantially constant pressure, means-for adjusting the dimensions ofsaid annular opening, fuel cutting blades rotatable over the l forward inner edge of said opening in the path of fuel therefrom, means for blowing a current of air forwardly over the inner edge of said opening, and means for automatically adjusting the velocity of said eurrent of air to correspond to the dimensions of said opening. I

12. Apparatus for burning fuels which comprises an annular feeding chamber recess having an annular inner edge and a mixing chamber forwardly thereof,A and a rearwardly extending supporting cylinder, an inner cylinder within said supporting cylinder and slidable longitudinally therein and having an inwardly tapering outer surface at its forward end in spaced relation to said annular edge and forming a feed orifice therewith, means for moving said inner cylinder longitudinally in said supporting cylinder to vary the\width of said annular orifice, means for forcing fuel to said annular chamber, andl means for blowing air through said inner cylinder over the inner edge of said orifice.

13. Apparatus for burning fuels which comprises an annular feeding chamber recess having an annular inner forward edge, and a. mixing chamber forwardly, thereof, and a rearwardly extending supporting cylinder, an inner cylinder slidable within said supporting cylinder and having a tapered outer edge in spaced relation to the edgelof said chamber recess and forming a feed orifice' therewith, means for sliding said inner cylinder to vary the width of said feed orifice, ro-

tatable cutter blades rotatable over the inner edge of said orice, means for forcing fuel to said annular chamber, means for blowing air through said inner cylinder over the edges of said orifice, and means for varying the velocity of said air in relation to the width of adjustable width, means for supplying fuel to said annular chamber under subst-antially constant pressure, cutter blades rotat- 'able over the'inner edge of said orifice, a fan and motor within said cylinder and driving said cutter blades, and means for controlling 'the speed ofsaid motor and fan in denite relation to the width of said fuel feed orifice. ln testimony whereof, I aiiix my signature.

EARL P. wETMoRE. 

